Functionality change based on stress-engineered components

ABSTRACT

A device includes at least one stress-engineered portion and at least one second portion. The stress-engineered portion includes at least one tensile stress layer having a residual tensile stress and at least one compressive stress layer having a residual compressive stress. The tensile stress layer and the compressive stress layer are mechanically coupled such that the at least one tensile stress layer and the at least one compressive stress layer are self-equilibrating. The stress-engineered portion is configured to fracture due to propagating cracks generated in response to energy applied to the stress-engineered portion. Fracture of the stress-engineered portion changes functionality of the device from a first function to a second function, different from the first function.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT

This invention is based upon work supported by DARPA under Contract No.HR0011-16-C-0087 DARPA-MTO-ICARUS-ONLYDUST. The Government has certainrights to this invention.

TECHNICAL FIELD

This disclosure relates generally to devices comprisingstress-engineered layers configured to fracture in response to anapplied energy and to related methods and systems.

BACKGROUND

Devices capable of fracturing in a controlled, triggerable manner areuseful in a variety of applications.

BRIEF SUMMARY

Some embodiments are directed to a device that includes at least onestress-engineered portion and at least one second portion. Thestress-engineered portion includes at least one tensile stress layerhaving a residual tensile stress and at least one compressive stresslayer having a residual compressive stress. The tensile stress layer andthe compressive stress layer are mechanically coupled such that the atleast one tensile stress layer and the at least one compressive stresslayer are self-equilibrating. The stress-engineered portion isconfigured to fracture due to propagating cracks generated in responseto energy applied to the stress-engineered portion. Fracture of thestress-engineered portion changes functionality of the device from afirst function to a second function, different from the first function.

Some embodiments involve a method of changing functionality of a device.The method includes fracturing a stress-engineered portion of thedevice. The stress-engineered portion comprises at least one tensilestress layer having a residual tensile stress and at least onecompressive stress layer having a residual compressive stress. Thetensile stress layer and the compressive stress layer are mechanicallycoupled such that the at least one tensile stress layer and the at leastone compressive stress layer are self-equilibrating. Thestress-engineered portion is configured to fracture in response due topropagating cracks generated in response to energy applied to thestress-engineered portion. Fracturing the stress-engineered portioncauses a functionality of the device to change from a first function toa second function, different from the first function.

The above summary is not intended to describe each embodiment or everyimplementation. A more complete understanding will become apparent andappreciated by referring to the following detailed description andclaims in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a device having a first portion and a second portion,wherein the first portion is a stress-engineered portion that isdesigned to self-destruct by fracturing in response to an applied energyin accordance with some embodiments;

FIG. 2 is a flow diagram illustrating a method of changing functionalityof a device in accordance with embodiments disclosed herein;

FIG. 3A illustrates a device in a first state that has astress-engineered portion and a second portion and a firstfunctionality;

FIG. 3B illustrates the device is a second state after thestress-engineered portion has self-destructed and having a secondfunctionality;

FIGS. 4A through 4C illustrate a device wherein self-destruction of thestress-engineered portion causes second and third components to comeinto contact in accordance with some embodiments;

FIGS. 5A and 5B illustrate a device wherein self-destruction of thestress-engineered portion decouples first and second components inaccordance with some embodiments;

FIGS. 6A and 6B illustrate an embodiment wherein fracturing of thestress-engineered portion opens (unblocks) an aperture in the secondportion in accordance with some embodiments;

FIGS. 7A through 7C illustrate a sieve wherein self-destruction of thestress-engineered portion causes a change in the functionality of thesieve in accordance with some embodiments;

FIGS. 8A and 8B illustrate an embodiment wherein fracturing of thestress-engineered portion blocks an aperture in the second portion;

FIGS. 9A and 9B illustrate an embodiment in which fracture of thestress-engineered portion connects two containers;

FIGS. 10A and 10B illustrate an embodiment in which fracture of thestress-engineered portion disconnects two containers;

FIGS. 11A and 11B illustrate an embodiment in which fracture of thestress-engineered portion causes the position of the second portion tochange;

FIGS. 12 and 12B illustrate another embodiment in which fracture of thestress-engineered portion causes the position of the second portion tochange;

FIGS. 13A and 13B provide an example in which fracture of thestress-engineered portion causes a change in the surface characteristicof the device;

FIGS. 14A and 14B provide an example in which fracture of thestress-engineered portion causes a change in the mechanical resonance ofthe device;

FIGS. 15A and 15B provide an example in which fracture of thestress-engineered portion causes the second portion to change shape;

FIGS. 16A and 16B illustrate the concept of volume control in accordancewith some embodiments;

FIGS. 17A and 17B illustrate first and second electrical components thatare disconnected when the stress-engineered portion self-destructs inaccordance with some embodiments;

FIGS. 18A and 18B illustrate a scenario wherein first and secondelectrical components are connected when the stress-engineered portionself-destructs in accordance with some embodiments;

FIGS. 19A and 19B provide an example in which fracture of thestress-engineered portion causes a change in the electrical resonance ofthe device in accordance with some embodiments;

FIGS. 20A and 20B provide an example in which fracture of thestress-engineered portion causes a change in reflectivity of the devicein accordance with some embodiments;

FIGS. 21A and 21B provide an example in which fracture of thestress-engineered portion causes a change in optical transmissivity ofthe device in accordance with some embodiments;

FIGS. 22A and 22B provide an example in which fracture of thestress-engineered portion causes a change in optical scattering of thedevice in accordance with some embodiments;

FIGS. 23A and 23B provide an example in which fracture of thestress-engineered portion causes a change in the wavelength pass band ofthe device in accordance with some embodiments;

FIGS. 24A to 24E illustrate a first methodology in which astress-engineered substrate is fabricated in accordance with someembodiments;

FIGS. 25A to 25E illustrate a second methodology in which astress-engineered substrate is fabricated in accordance with someembodiments; and

FIGS. 26A to 26E illustrate a third methodology in which astress-engineered substrate is fabricated in accordance with someembodiments.

The figures are not necessarily to scale. Like numbers used in thefigures refer to like components. However, it will be understood thatthe use of a number to refer to a component in a given figure is notintended to limit the component in another figure labeled with the samenumber.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Stress-engineered layer technology can be used to selectivelydisintegrate portions of a device in which some portions of the deviceare designed for controlled fracture while other portions of the deviceremain intact. By fracturing some of the portions of the device, thefunctionality of the device can be changed. The most basic change can beactivating or deactivating a device. Performance specifications can alsobe altered by selectively initiating fracture of some portions. Usingthis approach, the device's functionality can be changed to fit adifferent set of criteria or end result.

The process used in preparing the stress-engineered portion of thedevice, e.g., chemical tempering, imparts a large stress gradient withinthe thickness of the stress-engineered portion. This stored mechanicalenergy is abruptly released when an initial fracture is formed. Forexample, according to some implementations, the initial fracture iscaused when a localized area is heated. The rapid heating and subsequentcooling damage the stress-engineered part leading to the initialfracture which in turn leads to propagating fractures.

The stress-engineered portion may have any suitable size and/or shape,e.g., a planar shape, a curved shape, a cylinder, etc. In someembodiments the stress-engineered portion may be hollow such as a tubeor pipe.

FIG. 1 illustrates a device 100 having a first portion 101 and a secondportion 102, wherein the first portion 101 is a stress-engineeredportion that is designed to self-destruct by fracturing in response toan applied energy. In some implementations, the second portion 102 isdesigned to remain intact after the stress-engineered portion fractures.As shown in the cross sectional view of FIG. 1 the stress-engineeredportion 101 may be a structure including at least one tensile stresslayer 115 having a residual tensile stress and at least one compressivestress layer 116 having a residual compressive stress. Tensile stresslayer 115 and compressive stress layer 116 (collectively referred toherein as “stress-engineered layers”) can be operably integrallyconnected together such that residual tensile and compressive stressesare self-equilibrating and produce a stress gradient. As set forth inadditional detail below, the stress-engineered layers 116 and 115 may befabricated in a variety of ways. For example, in some embodiments, thestress-engineered portion may be fabricated by post-treating a materialusing strategies similar to glass tempering (e.g., by way of heat orchemical treatment), or by depositing the layers using, for examplechemical, vapor deposition techniques in which the deposition parameters(i.e., temperature, pressure, chemistry) are varied such that the layerscollectively contain a significant inbuilt stress gradient. Note thatthe arrangement of stress-engineered layers 116 and 115 indicated inFIG. 1 is not intended to be limiting in that one or morestress-engineered and/or non-stressed substrate layers may be disposedon and/or between the two stress-engineered layers.

The stress-engineered portion 101 is designed so that an applied energycauses a small initial crack to form. In response to the formation ofthe small initial crack, stress within the layers is released andnumerous fractures propagate in the layers from the initial crack. Thepropagating fractures cause the stress-engineered portion 101 of thedevice 100 to break into several or many fragments while the secondportion 102 of the device 100 remains intact. According to some aspects,the fragments of the stress-engineered portion may be quite small andnumerous. For example, the fragments may have length, width, and heightdimensions of less than about 900 μm, less than about 500 μm, or evenless than about 100 μm. Fracturing of the stress-engineered portion 101changes the functionality of the device 100. According to some aspects,an energy delivery component 120 can be attached to thestress-engineered portion. The energy delivery component is configuredto apply the energy that creates the initial crack to thestress-engineered portion 101.

Various methods may be used to fabricate the stress-engineered portion.One example approach involves thin film sputter deposition. In thin filmsputter deposition, generally two distinct regimes can be identifiedleading to very different film morphology and characteristics, andresult in either compressive or tensile stress. Metals are often usedbecause of functionality (e.g., electrical properties), their structuralqualities (e.g., ductility), and the fact that a conductive sputtertarget allows for a simple, high yield, glow discharge DC magnetronsputtering process. However, stress-engineered metal oxides and glasses(silicon oxides) can be sputtered as well; these insulating orsemiconducting films can be sputter deposited by either radiofrequency(RF) sputtering or by reactive sputtering in a mixed inert/reactive gasplasma (e.g. argon/oxygen). To achieve reliable fragmentation of thestress-engineered portion, according to some embodiments, processes forfabricating the stress-engineered portion involves adaptingstress-engineered thin film fabrication techniques with ion-exchangetempering to create stress profiles in glass (SiO2) substrates, e.g.,glass (SiO2) substrates.

FIG. 2 is a flow diagram illustrating a method of changing functionalityof a device in accordance with embodiments disclosed herein. The deviceincludes at least one stress-engineered portion and at least one secondportion. The stress-engineered portion comprises one or more tensilestress layers having residual tensile stress and one or more compressivestress layers having residual compressive stress. The tensile stresslayers and the compressive stress layers are mechanically coupled suchthat the tensile stress layers and the compressive stress layers areself-equilibrating.

An applied energy causes 210 an initial crack in the stress-engineeredportion of the device. In response to the initial crack, crackspropagate 220 from the initial crack through the stress-engineeredportion. The propagating cracks fracture 230 the stress-engineeredportion while the second portion remains substantially intact.Fracturing the stress-engineered portion without fracturing the secondportion causes the functionality of the device to change 240 from afirst function to a second function which is different from the firstfunction. In some embodiments, the fractured stress-engineered portionis removed from the device and the removal of the stress-engineeredportion changes the functionality of the device. In other embodiments,the fragments of the stress-engineered portion remain a part of thedevice and the presence of the fragments changes the functionality ofthe device.

FIG. 3A illustrates a device 300 a having a stress-engineered portion320 and a second portion 310 and having a first functionality. Thesecond portion 310 may be a portion that is not stress-engineered. Inthis example, devices 300 a, 300 b are illustrated as keys. Thestress-engineered portion 320 may be fabricated separately and bonded tothe second portion 310 in some implementations. Alternatively, bothportions 310, 320 of the device 300 a may be formed as an integral unitfollowed by a process that creates the tensile and compressive stressesin the material of the stress-engineered portion. FIG. 3B illustratesthe device 300 b after the stress-engineered portion 320 is fracturedinto pieces while the second portion 310 remains intact. Before thestress-engineered portion 320 is fractured, the device 300 a is a keythat has a first functionality, e.g., key 300 a can open lock A. Afterthe stress-engineered portion 320 is removed by fracturing, the device300 b is a key that has a second functionality which is different fromthe first functionality, e.g., key 300 b can open lock B.

Although the functionality change is illustrated in FIGS. 3A and 3Busing keys, the approaches disclosed herein are not limited to keys, butencompass any type of device whose functionality can be changed byremoving a portion while leaving another portion intact. In thedisclosed embodiments, the portion that is removed is astress-engineered portion that self-destructs by fracturing when crackspropagate from an initial crack created in response to an appliedenergy. The change in functionality may comprise a change in themechanical, electrical, and/or optical function of the device. FIGS. 4through 16 illustrate devices wherein the mechanical functionality ofthe device is changed when the stress-engineered self-destructs. FIGS.17 and 18 illustrate devices wherein the electrical functionality of thedevice is changed when the stress-engineered substrate fractures. FIGS.17 and 18 illustrate devices wherein the electrical functionality of thedevice is changed when the stress-engineered substrate fractures. FIGS.19 through 21 illustrate devices wherein the optical functionality ofthe device is changed when the stress-engineered substrate fractures.

In some implementations, self-destruction of the stress-engineeredportion by fracturing causes a change in mass and/or change in volume ofthe device. In some implementations, the stress-engineered portion isarranged such that fracturing of the stress-engineered portion causes achange in shape of the device without substantially changing the massand/or volume of the device.

According to some embodiments, illustrated in FIG. 4A, a triggermechanism 450 that applies energy to the stress-engineered portion 420to create the initial crack is disposed on the stress-engineered portion420. For example, the trigger mechanism 450 may be a heater that, whenactivated, heats the surface of the stress-engineered portion. Heatingthe stress-engineered portion followed by cooling creates the initialcrack from which the propagating cracks originate.

The trigger mechanism may supply mechanical energy, thermal energy,electrical energy, chemical energy, magnetic energy, and/or opticalenergy to create the initial fracture. The trigger mechanism may operatein response to a trigger signal that can be generated manually or by asensor configured to sense trigger stimuli. The trigger stimuli maycomprise one or more of electromagnetic radiation (e.g., radio frequency(RF) radiation, infrared (IR radiation), visible light, ultraviolet (UV)radiation, x-ray radiation, etc.), vibration, a chemical, vapor, gas,sound, temperature, passage of time, moisture, an environmentalcondition, etc. For embodiments in which the trigger stimulus is visiblelight, the sensor may be configured to generate the trigger signal inresponse to exposure to broadband light, such as sunlight or room light,or narrow band light, such as green, red, or blue visible light. Forexample, the green, red or blue light may be produced by a laser.

FIGS. 4A through 4C illustrate an embodiment wherein in its initialstate 400 a, the device includes a stress-engineered portion 420, asecond portion 410 and a third portion 430. FIG. 4A shows the device 400that is arranged such that the stress-engineered portion 420 is disposedbetween the second portion 410 and the third portion 430. A triggermechanism 450 is disposed on the stress-engineered portion 420.

FIG. 4B shows the device in state 400 b just after the stress-engineeredportion 420 has self-destructed by fracturing. The fractures propagatingin the stress-engineered portion 420 propagate to the trigger mechanism450 and also destroy the trigger mechanism along with the portion 420.With the stress-engineered portion 420 removed, the second portion 410moves toward the third portion 430 along the direction indicated by thearrow.

FIG. 4C shows the device in state 400 c wherein second portion 410 iscontacting the third portion 430. According to some implementations, thesecond portion 410 and the third portion 430 may comprise electricalcontacts which are separated by the presence of the stress-engineeredportion 430. After the stress-engineered portion 420 self-destructs, thesecond portion 410 makes electrical contact with the third portion 430.

FIGS. 5A and 5B illustrate an embodiment wherein self-destruction of thestress-engineered portion separates the second portion 510 from a thirdportion. FIG. 5A illustrates a device in its initial state 500 a, thedevice includes a second portion 510, a third portion 530, and astress-engineered portion 520 that connects the second portion 510 andthe third portion 530.

FIG. 5B shows the device in state 500 b after the stress-engineeredportion 520 has self-destructed by fracturing. With thestress-engineered portion 520 removed, the second portion 510 isde-coupled from the third portion 530. According to someimplementations, the second portion 510 and the third portion 530 maycomprise electrical contacts which are electrically connected by thepresence of the stress-engineered portion 520. After thestress-engineered portion 520 self-destructs, the second portion 510 iselectrically disconnected from the third portion 530.

In some embodiments, the device is configured such that fracture of thestress-engineered portion unblocks an aperture as illustrated in FIGS. 6and 7. FIGS. 6A and 6B illustrate an embodiment wherein fracturing ofthe stress-engineered portion 620 opens (unblocks) an aperture in thesecond portion 610. FIG. 6A illustrates a device in its initial state600 a, the device includes a second portion 610 and a stress-engineeredportion 620 blocking an aperture 690 in the second portion 610.

FIG. 6B shows the device in state 600 b after the stress-engineeredportion 6520 has self-destructed by fracturing. With thestress-engineered portion 620 removed, the aperture 690 in the secondportion 610 is unblocked.

FIGS. 7A through 7C illustrate an embodiment in which the device is asieve. FIG. 7A illustrates a device in its initial state 700 a, thedevice includes a second portion 710 and a stress-engineered portions720-1, 720-2 partially blocking apertures 790 in the second portion 710.In state 700 a, particles having a first diameter can pass throughapertures 790 a of the sieve. FIG. 7B shows the device in state 700 bafter the stress-engineered portion 720-1 has self-destructed byfracturing. With the stress-engineered portion 720-1 removed, theapertures 790 b in the sieve are larger and allow the passage ofparticles having a second diameter, which is larger than the firstdiameter, to pass through the sieve. FIG. 7C shows the device in state700 c after the stress-engineered portion 720-2 has self-destructed byfracturing. With the stress-engineered portion 720-2 removed, theapertures 790 c in the sieve are larger and allow the passage ofparticles having a third diameter, which is larger than the seconddiameter, to pass through the sieve. The device may include one or moreadditional stress-engineered portions, wherein removal of the one ormore additional stress-engineered portions changes the functionality ofthe sieve to pass larger diameter particles.

FIGS. 8A and 8B illustrate an embodiment wherein fracturing of thestress-engineered portion 820 blocks an aperture 890 in the secondportion 810. FIG. 8A illustrates a device in its initial state 800 a,the device includes a second portion 810 having an aperture 890 and astress-engineered portion 820.

FIG. 8B shows the device in state 800 b after the stress-engineeredportion 820 has self-destructed by fracturing. Fragments 825 of thestress-engineered portion 820 fall in front of aperture 890, blockingthe aperture 890.

In some embodiments, the stress-engineered portion is arranged such thatfracture of the stress-engineered portion is configured to causeconnection or disconnection of first and second containers.

FIGS. 9A and 9B illustrate an embodiment in which fracture of thestress-engineered portion connects two containers. FIG. 9A illustrates adevice in a first state 900 a wherein the second portion 910 forms anenclosure that is separated into two containers 961, 962 by thestress-engineered portion 920.

FIG. 9B shows the device in state 900 b after the stress-engineeredportion 920 has self-destructed by fracturing. Fracturing thestress-engineered portion connects the two containers 961, 962.

FIGS. 10A and 10B illustrate an embodiment in which fracture of thestress-engineered portion disconnects two containers. FIG. 10Aillustrates a device in a first state 1000 a wherein the second portion1010 is container having an interior volume 1071 fluidically connectedto another the interior volume 1072 of a second enclosure 1030.Stress-engineered portion 1020 comprises a tube that fluidicallyconnects the interior volumes 1071, 1072 of the enclosures 1010 and1030.

FIG. 10B shows the device in state 1000 b after the stress-engineeredportion 1020 has self-destructed by fracturing. Fracturing thestress-engineered portion 1020 fluidically disconnects the twocontainers 1010, 1030.

According to some implementations, the self-destruction of thestress-engineered portion can cause or allow the second portion tochange position. For example, the self-destruction of thestress-engineered portion can change the mobility of the second portion,causing or allowing the second portion to become mobile.

FIGS. 11A and 11B illustrate an embodiment in which fracture of thestress-engineered portion causes the position of the second portion tochange. FIG. 11A illustrates a device in a first state 1100 a whereinthe stress-engineered portion 1120 and the second portion 1110 arebalanced on a fulcrum 1150. The second portion 1110 is in a positionthat is a distance d1 from a reference point which in this example isthe center of the fulcrum.

FIG. 11B shows the device in state 1100 b after the stress-engineeredportion 1120 has self-destructed by fracturing. Fracturing thestress-engineered portion 1120 causes the second portion 1110 to movealong the direction of arrow 1199 to a position that is a distance d2from the reference point.

FIGS. 12A and 12B provide another example in which fracture of thestress-engineered portion causes the position of the second portion tochange. FIG. 12A illustrates a device in a first state 1200 a whereinthe stress-engineered portion 1220 is a peg inserted into a tapered holeof an inclined plane 1240. The second portion 1210 is held in place bythe stress-engineered portion 1220 at position (x=x1, y=y1).

FIG. 12B shows the device in state 1200 b after the stress-engineeredportion 1220 has self-destructed by fracturing. Fracturing thestress-engineered portion 1220 allows the second portion 1210 to movealong the inclined plane 1240 to a position (x=x2, y=y2), where x1≠x2and y1≠y2.

In some embodiments, the stress-engineered portion is arranged such thatself-destruction of the stress-engineered portion causes a change in asurface characteristic of the device.

FIGS. 13A and 13B provide example in which fracture of thestress-engineered portion causes a change in the surface characteristicof the device. FIG. 13A illustrates a device in a first state 1300 awherein the stress-engineered portion 1320 is a layer having a smoothouter surface 1321 disposed on the second portion 1310.

FIG. 13B shows the device in state 1300 b after the stress-engineeredportion 1320 has self-destructed by fracturing. Fracturing thestress-engineered portion 1320 exposes a microstructured surface 1311 onthe second portion 1310 and changes the surface structure of the devicefrom smooth to rough.

According to some embodiments, fracturing the stress-engineered portioncauses a change in the mechanical resonance of the device.

FIGS. 14A and 14B provide example in which fracture of thestress-engineered portion causes a change in the mechanical resonance ofthe device. FIG. 14A illustrates a device that is a tuning fork in afirst state 1400 a. In the first state 1400 a, the tuning fork has afirst mechanical resonance.

FIG. 14B shows the tuning fork in state 1400 b after thestress-engineered portion 1420 has self-destructed by fracturing.Fracturing the stress-engineered portion 1420 changes the mechanicalresonance of the tuning fork from the first mechanical resonance to adifferent second mechanical resonance.

According to some embodiments, fracturing the stress-engineered portioncauses the second portion to change shape.

FIGS. 15A and 15B provide example in which fracture of thestress-engineered portion 1520 causes the second portion 1510 to changeshape. FIG. 15A illustrates a device in a first state 1500 a wherein thesecond portion 1510 is a flexible film disposed over a curved surface ofa stress-engineered portion.

FIG. 15B shows the device in a second state 1500 b after thestress-engineered portion 1520 has self-destructed by fracturing.Fracturing the stress-engineered portion 1520 allows the flexible film1510 to resume its previously flat shape.

According to some embodiments, a stress-engineered portion providesvolume control in the event that a second portion is broken.

FIGS. 16A and 16B illustrate the concept of volume control in accordancewith some embodiments. FIG. 16A illustrates a device in a first state1600 a wherein the second portion 1610 which may be a second structure,at least partially encloses an interior volume 1691. A third portion1630 encloses a back-up volume 1692. Stress-engineered portion 1620 isdisposed between volume 1691 and volume 1692.

When the second portion 1610 is fractured, the fractures within thesecond portion 1610 do not result in propagating fractures that destroythe second portion 1610. The energy that causes the fracturing of thesecond portion 1610 is transmitted through the second portion 1610 tothe stress-engineered portion 1620 causing the stress-engineered portion1620 to self-destruct.

FIG. 16B shows the device in a second state 1600 b after the secondportion 1610 is fractured and the stress-engineered portion 1620 hasself-destructed. Fracture of the second portion compromises volume 1681.Self-destruction of the stress-engineered portion 1620 opens backupvolume 1692. With the self-destruction of the stress-engineered portion1620, the backup volume 1692 is fluidically coupled to what is left ofvolume 1691 such that anything previously contained in volume 1691 isnow contained by backup volume 1692.

Some embodiments are directed to a device that includes astress-engineered portion and a second portion wherein self-destructionof the stress-engineered portion changes an electrical functionality ofthe device. For example, self-destruction of the stress-engineeredportion may electrically connect or electrically disconnect a firstelectrical component from a second electrical component. In someimplementations, electrically connecting or electrically disconnecting afirst electrical component from a second electrical component changesdata stored in the device.

FIGS. 17A and 17B illustrate first and second electrical components thatare disconnected when the stress-engineered portion self-destructs. FIG.17A shows an electrical device in a first state 1700 a wherein thecircuit 1710 includes resistors R1 and R2 that are electricallyconnected in parallel by stress-engineered portion 1710. In thisembodiment, stress-engineered portion 1720 comprises an electricallyconductive trace that electrically connects R1 and R2.

FIG. 17B shows the device in a second state 1700 b after thestress-engineered portion 1720 has self-destructed. Fracture of thestress-engineered portion 1720 disconnects R1 from R2.

FIGS. 18A and 18B illustrate a scenario wherein first and secondelectrical components are connected when the stress-engineered portionself-destructs. FIG. 18A shows an electrical device in a first state1800 a wherein the circuit 1810 includes a resistor R1 and a switch S1.Switch S1 includes stress-engineered portion 1820 which maintains theswitch S1 in the open position. When S1 is open, R1 and R2 areelectrically disconnected.

FIG. 18B shows the device in a second state 1800 b after thestress-engineered portion 1820 has self-destructed. Fracture of thestress-engineered portion 1820 closes switch S1, electrically connectingR1 and R2.

According to some embodiments, fracturing the stress-engineered portioncauses a change in the electrical resonance of the device.

FIGS. 19A and 19B provide example in which fracture of thestress-engineered portion causes a change in the electrical resonance ofthe device. FIG. 19A illustrates a tank circuit 1910 in a first state1900 a. In state 1900 a, the tank circuit 1910 has a first electricalresonance which is based on the values of the inductance L and thecapacitance C of the tank circuit. When the device 1910 is in state 1900a, the capacitance of the tank circuit, C, is equal to the sum of theparallel connected capacitors C1 and C2. The stress-engineered portion1920 electrically connects C1 and C2.

FIG. 19B shows the tank circuit 1910 in state 1900 b after thestress-engineered portion 1920 has self-destructed by fracturing.Fracturing the stress-engineered portion 1920 electrically disconnectscapacitor C2 from the tank circuit 1910. In state 1900 b, thecapacitance of the tank circuit is C1 and the tank circuit 1910 has asecond resonance that is different from the first resonance

Some embodiments are directed to a device that includes astress-engineered portion and a second portion wherein self-destructionof the stress-engineered portion changes an optical functionality of thedevice. For example, as illustrated in FIGS. 20A through 21B,self-destruction of the stress-engineered portion may change opticaltransmissivity or reflectivity of the device.

FIGS. 20A and 20B provide example in which fracture of thestress-engineered portion causes a change in optical reflectivity of thedevice. FIG. 20A illustrates a device in a first state 2000 a having astress-engineered optical layer 2020 that is optically opaque and asecond layer 2010 that is optically reflective. In state 2000 a, theoptically opaque stress-engineered layer 2020 prevents light 2099 frombeing reflected by reflecting layer 2010.

FIG. 20B shows the device in state 2000 b after the stress-engineeredportion 1920 has self-destructed by fracturing. In state 2000 b, light2099 is reflected by layer 2010.

FIG. 21A illustrates a device in a first state 2100 a having astress-engineered optical layer 2120 that is optically opaque and asecond layer 2110 that is optically transmissive. In state 2100 a, theoptically opaque stress-engineered layer 2120 prevents light 2199 frombeing transmitted by transmissive layer 2110.

FIG. 21B shows the device in state 2100 b after the stress-engineeredportion 2020 has self-destructed by fracturing. In state 2100 b, light2199 is reflected by layer 2110.

In some embodiments, as illustrated in FIGS. 22A and 22B,self-destruction of the stress-engineered portion may change opticalscattering of the device.

FIG. 22A illustrates a device in a first state 2200 a having astress-engineered optical layer 2220 that exhibits low scattering and issandwiched between a second layer 2210 and a third layer 2230. In state2200 a, the device transmits light 2299 with relatively low scattering.

FIG. 22B shows the device in state 2200 b after the stress-engineeredlayer 2220 has self-destructed by fracturing. In state 2200 b, thefragments 2225 of the stress-engineered layer are trapped between thesecond and third layers 2210, 2230. The trapped fragments 2225 providescattering sites for light 2299 passing through the device. Due to thetrapped fragments 2225, in state 2200 a, the device transmits light 2299with relatively higher scattering.

According to some embodiments, self-destruction of the stress-engineeredlayer causes a change in the optical band pass of the device.

FIG. 23A illustrates a device in a first state 2300 a having astress-engineered optical layer 2320 that has a narrow optical bandpassarranged on a second layer 2310 that has a wide optical bandpass. Instate 2300 a, the device transmits light within the narrow bandpass ofthe stress-engineered layer 2320 and blocks other wavelengths.

FIG. 23B shows the device in state 2300 b after the stress-engineeredlayer 2320 has self-destructed by fracturing. In state 2300 b, thedevice transmits light within the wide bandpass of the second layer2310.

FIGS. 24A to 24E illustrate a first methodology in which astress-engineered support substrate 2410A is built up by patterned SiO₂stress-engineered support substrates generated entirely using plasmavapor deposition (PVD) techniques. This method provides a high degree ofcontrol over the specific stress profile generated in thestress-engineered support substrate and provides for continuous controlover glass formulation and morphology through the thickness dimension ofthe stress-engineered support substrate. A wafer 2400 (e.g., silicon orother material) is coated with a release layer 2410, most likely ametal. In FIG. 24B, a thick liftoff mask 2420 is then patterned onrelease layer 2410 such that mask 2420 defines an opening 2422. Notethat wafer 2400, release layer 2410, and mask 2420 form a sacrificialstructure. Referring to FIGS. 24C and 24D, PVD processing is then usedto create the stress engineered layers 2410A-1 and 2410A-2 in opening2422, placing stresses in the deposited substrate material 2430-1 and2430-2, for example, by altering the process parameters (e.g., usingdifferent temperatures T1 and T2 and/or pressures P1 and P2). Finally,as indicated in FIG. 24E, the mask is then lifted off, andstress-engineered substrate 2410A is singulated (removed) from theremaining sacrificial structure by under-etching the release layer.

FIGS. 25A to 25E illustrate a second methodology in which astress-engineered support substrate 2510B is built up by patterned SiO₂on a thin glass core using PVD techniques. This methodology provides ahigh degree of control over the specific stress profile generated in thestress-engineered support substrate. Referring to FIG. 25A, the processbegins using a substantially unstressed glass core substrate 2510B-0having a thickness T0 in the range of 25 μm and 100 μm. Suitable glasscore substrates are currently produced by Schott North America, Inc. ofElmsford, N.Y., USA). Referring to FIGS. 25B to 25E, SiO₂ is thendeposited on alternating sides of core substrate 2510B-0 via PVD usingmethods similar to those described above. Specifically, FIG. 25B showsthe deposition of material 630-1 in a manner that formsstress-engineered layer 2510B-11 on core substrate 2510B-0. FIG. 25Cshows the deposition of material 2530-2 in a manner that formsstress-engineered layer 2510B-21 on an opposite side of core substrate2510B-0. FIG. 25C shows the subsequent deposition of material 2530-1 ina manner that forms stress-engineered layer 2510B-12 on core layer2510B-11, and FIG. 25E shows the deposition of material 2530-2 in amanner that forms stress-engineered layer 2510B-22 layer 2510B-21. FIG.25E shows completed stress-engineered support substrate 2510B includingcore substrate (central, substantially unstressed layer) 2410B-0 withstress-engineered layers 2510B-11, 2510B-12, 2510B-21 and 2510B-22formed thereon.

FIGS. 26A to 26E illustrate a third methodology in which astress-engineered substrate 2610C is produced by subjecting a coresubstrate to one of an ion-exchange tempering treatment, a chemicaltreatment and a thermal treatment. Specifically, FIGS. 26A to 26Eillustrate an exemplary ion-exchange tempering treatment during whichvarious stress profiles are introduced in a core substrate viamolten-salt ion exchange. FIG. 26A shows a core substrate 2610C-0 over avat 2650 containing a molten-salt solution 2655. FIG. 26B shows coresubstrate 2610C-0 immediately after submersion in molten-salt solution2655, FIG. 26C shows core substrate 2610C-0 after a first time period ofsubmersion in molten-salt solution 2655 in which a firststress-engineered layer 2610C-1 is formed, and FIG. 26D shows thestructure after a second time period of submersion in molten-saltsolution 2655 in which a second stress-engineered layer 2610C-2 isformed on first stress-engineered layer 2610C-1. FIG. 26E showscompleted stress-engineered support substrate 2600C including centralcore substrate 26710C-0 and stress-engineered layers 2610C-1 and2610C-2.

According to a fourth methodology, a hybrid of the above second andthird methods is employed in which diced, thin glass core substrates areion-exchange tempered, and then multiple layers of SiO2 are deposited onthe tempered substrates to further increase the induced stresses.

Unless otherwise indicated, all numbers expressing feature sizes,amounts, and physical properties used in the specification and claimsare to be understood as being modified in all instances by the term“about.” Accordingly, unless indicated to the contrary, the numericalparameters set forth in the foregoing specification and attached claimsare approximations that can vary depending upon the desired propertiessought to be obtained by those skilled in the art utilizing theteachings disclosed herein. The use of numerical ranges by endpointsincludes all numbers within that range (e.g. 1 to 5 includes 1, 1.5, 2,2.75, 3, 3.80, 4, and 5) and any range within that range.

Various modifications and alterations of the embodiments discussed abovewill be apparent to those skilled in the art, and it should beunderstood that this disclosure is not limited to the illustrativeembodiments set forth herein. The reader should assume that features ofone disclosed embodiment can also be applied to all other disclosedembodiments unless otherwise indicated. It should also be understoodthat all U.S. patents, patent applications, patent applicationpublications, and other patent and non-patent documents referred toherein are incorporated by reference, to the extent they do notcontradict the foregoing disclosure.

1. A device, comprising: at least one stress-engineered portion,comprising: at least one tensile stress layer having a residual tensilestress; and at least one compressive stress layer having a residualcompressive stress and being mechanically coupled to the at least onetensile stress layer such that the at least one tensile stress layer andthe at least one compressive stress layer are self-equilibrating, thestress-engineered portion configured to fracture due to propagatingcracks generated in response to energy applied to the stress-engineeredportion; and at least one second portion, wherein fracture of thestress-engineered portion changes functionality of the device from afirst function to a second function, different from the first function.2. The device of claim 1, further comprising trigger mechanism attachedto the stress-engineered portion and configured to apply the energy tothe stress-engineered portion that creates an initial crack from whichat least some of the propagating cracks originate.
 3. The device ofclaim 1, wherein the stress-engineered portion is arranged such thatfracture of the stress-engineered portion is configured to cause thesecond portion to contact a third portion of the device.
 4. The deviceof claim 1, wherein the stress-engineered portion is arranged such thatfracture of the stress-engineered portion is configured to causedisconnection the second portion from a third portion of the device. 5.The device of claim 1, wherein the stress-engineered portion is arrangedsuch that fracture of the stress-engineered portion is configured tocause one or more of a change in mass and a change in volume of thedevice.
 6. The device of claim 1, wherein the stress-engineered portionis arranged such that fracture of the stress-engineered portion isconfigured to cause a change in shape of the device withoutsubstantially changing mass or volume of the device.
 7. The device ofclaim 1, wherein the stress-engineered portion is arranged such thatfracture of the stress-engineered portion is configured to change amechanical functionality of the device.
 8. The device of claim 1,wherein the stress-engineered portion is arranged such that fracture ofthe stress-engineered portion is configured to cause at least one ofblocking and unblocking of an aperture.
 9. The device of claim 1,wherein the stress-engineered portion is arranged such that fracture ofthe stress-engineered portion is configured to cause at least one ofconnection and disconnection of first and second containers.
 10. Thedevice of claim 1, wherein the stress-engineered portion is arrangedsuch that fracture of the stress-engineered portion is configured tocause a change in position of the first portion.
 11. The device of claim1, wherein the stress-engineered portion is arranged such that fractureof the stress-engineered portion is configured to cause a change inmobility of the first portion.
 12. The device of claim 1, wherein thestress-engineered portion is arranged such that fracture of thestress-engineered portion is configured to cause a change in a surfacecharacteristic of the device.
 13. The device of claim 1, wherein thestress-engineered portion is arranged such that fracture of thestress-engineered portion is configured to cause a change in at leastone of an electrical and a mechanical resonance of the device.
 14. Thedevice of claim 1, wherein the stress-engineered portion is arrangedsuch that fracture of the stress-engineered portion is configured tochange an electrical functionality of the device.
 15. The device ofclaim 1, wherein the stress-engineered portion is arranged such thatfracture of the stress-engineered portion is configured to cause atleast one of electrical connection and electrical disconnection of afirst electrical component and a second electrical component.
 16. Thedevice of claim 15, wherein the electrical connection or electricaldisconnection of the first electrical component and the secondelectrical component changes data stored in the device.
 17. The deviceof claim 1, wherein the stress-engineered portion is arranged such thatfracture of the stress-engineered portion is configured to change anoptical functionality of the device.
 18. The device of claim 1, whereinthe stress-engineered portion is arranged such that fracture of thestress-engineered portion is configured to cause a change in at leastone of optical transmissivity, optical reflectivity, optical scattering,and optical bandpass of the device.
 19. The device of claim 1, whereinthe second portion reverts to a previous shape after thestress-engineered portion fractures.
 20. The device of claim 1, whereinmechanical compromise of the second portion triggers fracture of thestress-engineered portion.
 21. A method of changing functionality of adevice comprising: fracturing a stress-engineered portion of the device,the second stress-engineered portion comprising: at least one tensilestress layer having a residual tensile stress; and at least onecompressive stress layer having a residual compressive stress and beingmechanically coupled to the at least one tensile stress layer such thatthe at least one tensile stress layer and the at least one compressivestress layer are self-equilibrating, the stress-engineered portionconfigured to fracture in response due to propagating cracks generatedin response to energy applied to the stress-engineered portion; inresponse to the fracturing of the stress-engineered portion, causing afunctionality of the device to change from a first function to a secondfunction, different from the first function.